Message ID | 20221111193639.346992-5-jlayton@kernel.org (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | filelock: WARN when @filp and fl_file don't match | expand |
On Fri, 2022-11-11 at 14:36 -0500, Jeff Layton wrote: > vfs_lock_file, vfs_test_lock and vfs_cancel_lock all take both a struct > file argument and a file_lock. The file_lock has a fl_file field in it > howevever and it _must_ match the file passed in. > > While most of the locks.c routines use the separately-passed file > argument, some filesystems rely on fl_file being filled out correctly. > > I'm working on a patch series to remove the redundant argument from > these routines, but for now, let's ensure that the callers always set > this properly by issuing a WARN_ON_ONCE if they ever don't match. > > Cc: Chuck Lever <chuck.lever@oracle.com> > Cc: Trond Myklebust <trondmy@hammerspace.com> > Signed-off-by: Jeff Layton <jlayton@kernel.org> > --- > fs/locks.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/fs/locks.c b/fs/locks.c > index 607f94a0e789..5876c8ff0edc 100644 > --- a/fs/locks.c > +++ b/fs/locks.c > @@ -2146,6 +2146,7 @@ SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd) > */ > int vfs_test_lock(struct file *filp, struct file_lock *fl) > { > + WARN_ON_ONCE(filp != fl->fl_file); > if (filp->f_op->lock) > return filp->f_op->lock(filp, F_GETLK, fl); > posix_test_lock(filp, fl); > @@ -2295,6 +2296,7 @@ int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock *flock) > */ > int vfs_lock_file(struct file *filp, unsigned int cmd, struct file_lock *fl, struct file_lock *conf) > { > + WARN_ON_ONCE(filp != fl->fl_file); > if (filp->f_op->lock) > return filp->f_op->lock(filp, cmd, fl); > else > @@ -2663,6 +2665,7 @@ void locks_remove_file(struct file *filp) > */ > int vfs_cancel_lock(struct file *filp, struct file_lock *fl) > { > + WARN_ON_ONCE(filp != fl->fl_file); > if (filp->f_op->lock) > return filp->f_op->lock(filp, F_CANCELLK, fl); > return 0; Oops, I meant to cc linux-fsdevel here too. I'll plan to do that on the next posting (assuming that I need to do one). Cheers,
diff --git a/fs/locks.c b/fs/locks.c index 607f94a0e789..5876c8ff0edc 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -2146,6 +2146,7 @@ SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd) */ int vfs_test_lock(struct file *filp, struct file_lock *fl) { + WARN_ON_ONCE(filp != fl->fl_file); if (filp->f_op->lock) return filp->f_op->lock(filp, F_GETLK, fl); posix_test_lock(filp, fl); @@ -2295,6 +2296,7 @@ int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock *flock) */ int vfs_lock_file(struct file *filp, unsigned int cmd, struct file_lock *fl, struct file_lock *conf) { + WARN_ON_ONCE(filp != fl->fl_file); if (filp->f_op->lock) return filp->f_op->lock(filp, cmd, fl); else @@ -2663,6 +2665,7 @@ void locks_remove_file(struct file *filp) */ int vfs_cancel_lock(struct file *filp, struct file_lock *fl) { + WARN_ON_ONCE(filp != fl->fl_file); if (filp->f_op->lock) return filp->f_op->lock(filp, F_CANCELLK, fl); return 0;
vfs_lock_file, vfs_test_lock and vfs_cancel_lock all take both a struct file argument and a file_lock. The file_lock has a fl_file field in it howevever and it _must_ match the file passed in. While most of the locks.c routines use the separately-passed file argument, some filesystems rely on fl_file being filled out correctly. I'm working on a patch series to remove the redundant argument from these routines, but for now, let's ensure that the callers always set this properly by issuing a WARN_ON_ONCE if they ever don't match. Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Trond Myklebust <trondmy@hammerspace.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> --- fs/locks.c | 3 +++ 1 file changed, 3 insertions(+)